If it's that quick (and not analysed at the end of the day), it'd be ideal. Just like overstepping - immediate no ball.

I honestly don't think it's going to reach this point for a while. Far too complex for an automated system. It'll be a tool for the match referee/some other official to use and keep tabs on, and warnings etc can be handed out on when he/she thinks the evidence against the "bowler" is damning enough.